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- #ifndef __KERN_FS_SFS_SFS_H__
- #define __KERN_FS_SFS_SFS_H__
-
- #include <defs.h>
- #include <mmu.h>
- #include <list.h>
- #include <sem.h>
- #include <unistd.h>
-
- /*
- * Simple FS (SFS) definitions visible to ucore. This covers the on-disk format
- * and is used by tools that work on SFS volumes, such as mksfs.
- */
-
- #define SFS_MAGIC 0x2f8dbe2a /* magic number for sfs */
- #define SFS_BLKSIZE PGSIZE /* size of block */
- #define SFS_NDIRECT 12 /* # of direct blocks in inode */
- #define SFS_MAX_INFO_LEN 31 /* max length of infomation */
- #define SFS_MAX_FNAME_LEN FS_MAX_FNAME_LEN /* max length of filename */
- #define SFS_MAX_FILE_SIZE (1024UL * 1024 * 128) /* max file size (128M) */
- #define SFS_BLKN_SUPER 0 /* block the superblock lives in */
- #define SFS_BLKN_ROOT 1 /* location of the root dir inode */
- #define SFS_BLKN_FREEMAP 2 /* 1st block of the freemap */
-
- /* # of bits in a block */
- #define SFS_BLKBITS (SFS_BLKSIZE * CHAR_BIT)
-
- /* # of entries in a block */
- #define SFS_BLK_NENTRY (SFS_BLKSIZE / sizeof(uint32_t))
-
- /* file types */
- #define SFS_TYPE_INVAL 0 /* Should not appear on disk */
- #define SFS_TYPE_FILE 1
- #define SFS_TYPE_DIR 2
- #define SFS_TYPE_LINK 3
-
- /*
- * On-disk superblock
- */
- struct sfs_super {
- uint32_t magic; /* magic number, should be SFS_MAGIC */
- uint32_t blocks; /* # of blocks in fs */
- uint32_t unused_blocks; /* # of unused blocks in fs */
- char info[SFS_MAX_INFO_LEN + 1]; /* infomation for sfs */
- };
-
- /* inode (on disk) */
- struct sfs_disk_inode {
- uint32_t size; /* size of the file (in bytes) */
- uint16_t type; /* one of SYS_TYPE_* above */
- uint16_t nlinks; /* # of hard links to this file */
- uint32_t blocks; /* # of blocks */
- uint32_t direct[SFS_NDIRECT]; /* direct blocks */
- uint32_t indirect; /* indirect blocks */
- // uint32_t db_indirect; /* double indirect blocks */
- // unused
- };
-
- /* file entry (on disk) */
- struct sfs_disk_entry {
- uint32_t ino; /* inode number */
- char name[SFS_MAX_FNAME_LEN + 1]; /* file name */
- };
-
- #define sfs_dentry_size \
- sizeof(((struct sfs_disk_entry *)0)->name)
-
- /* inode for sfs */
- struct sfs_inode {
- struct sfs_disk_inode *din; /* on-disk inode */
- uint32_t ino; /* inode number */
- bool dirty; /* true if inode modified */
- int reclaim_count; /* kill inode if it hits zero */
- semaphore_t sem; /* semaphore for din */
- list_entry_t inode_link; /* entry for linked-list in sfs_fs */
- list_entry_t hash_link; /* entry for hash linked-list in sfs_fs */
- };
-
- #define le2sin(le, member) \
- to_struct((le), struct sfs_inode, member)
-
- /* filesystem for sfs */
- struct sfs_fs {
- struct sfs_super super; /* on-disk superblock */
- struct device *dev; /* device mounted on */
- struct bitmap *freemap; /* blocks in use are mared 0 */
- bool super_dirty; /* true if super/freemap modified */
- void *sfs_buffer; /* buffer for non-block aligned io */
- semaphore_t fs_sem; /* semaphore for fs */
- semaphore_t io_sem; /* semaphore for io */
- semaphore_t mutex_sem; /* semaphore for link/unlink and rename */
- list_entry_t inode_list; /* inode linked-list */
- list_entry_t *hash_list; /* inode hash linked-list */
- };
-
- /* hash for sfs */
- #define SFS_HLIST_SHIFT 10
- #define SFS_HLIST_SIZE (1 << SFS_HLIST_SHIFT)
- #define sin_hashfn(x) (hash32(x, SFS_HLIST_SHIFT))
-
- /* size of freemap (in bits) */
- #define sfs_freemap_bits(super) ROUNDUP((super)->blocks, SFS_BLKBITS)
-
- /* size of freemap (in blocks) */
- #define sfs_freemap_blocks(super) ROUNDUP_DIV((super)->blocks, SFS_BLKBITS)
-
- struct fs;
- struct inode;
-
- void sfs_init(void);
- int sfs_mount(const char *devname);
-
- void lock_sfs_fs(struct sfs_fs *sfs);
- void lock_sfs_io(struct sfs_fs *sfs);
- void unlock_sfs_fs(struct sfs_fs *sfs);
- void unlock_sfs_io(struct sfs_fs *sfs);
-
- int sfs_rblock(struct sfs_fs *sfs, void *buf, uint32_t blkno, uint32_t nblks);
- int sfs_wblock(struct sfs_fs *sfs, void *buf, uint32_t blkno, uint32_t nblks);
- int sfs_rbuf(struct sfs_fs *sfs, void *buf, size_t len, uint32_t blkno, off_t offset);
- int sfs_wbuf(struct sfs_fs *sfs, void *buf, size_t len, uint32_t blkno, off_t offset);
- int sfs_sync_super(struct sfs_fs *sfs);
- int sfs_sync_freemap(struct sfs_fs *sfs);
- int sfs_clear_block(struct sfs_fs *sfs, uint32_t blkno, uint32_t nblks);
-
- int sfs_load_inode(struct sfs_fs *sfs, struct inode **node_store, uint32_t ino);
-
- #endif /* !__KERN_FS_SFS_SFS_H__ */
-
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